Open AccessHighly-sensitive Refractometer Based on a D-shaped Fiber Bragg Grating Integrated into A Loop-mirror Optical Fiber Laser
Author(s) -
Binh Pham Thanh,
Thuy Van Nguyen,
Van Hoi Pham,
Huy Bui,
Thi Hong Cam Hoang,
Thuy Chi,
Anh Tuấn Nguyễn
Publication year - 2021
Publication title -
communications in physics/communications in physics
Language(s) - English
Resource type - Journals
eISSN - 2815-5947
pISSN - 0868-3166
DOI - 10.15625/0868-3166/16014
Subject(s) - fiber bragg grating , optics , materials science , refractometer , graded index fiber , fiber optic sensor , laser , fiber laser , optical fiber , polarization maintaining optical fiber , phosfos , long period fiber grating , optoelectronics , refractive index , wavelength , physics
In this paper, we report a new type of refractometer based on a D-shaped fiber Bragg grating (FBG) integrated in a loop-mirror optical fiber laser. This proposed sensor is used in wavelength interrogation method, in which the D-shaped FBG is applied as a refractive index (RI) sensing probe and a mirror to select mode of laser. The D-shaped FBG is prepared by the removal of a portion of the fiber cladding covering the FBG by means of side-polishing technique. The D-shaped FBG sensing probe integrated in a loop-mirror optical fiber laser with saturated pump technique, the characteristics of sensing signals have been improved to obtain stable intensity, narrower bandwidth and higher optical signal-to-noise ratio compare to normal reflection configuration. The limit of detection (LOD) of this sensor can be achieved to 2.95 x 10-4 RIU in the refractive index (RI) range of 1.42-1.44. Accordingly, we believe that the proposed refractometer has a huge potential for applications in biochemical-sensing technique.